Digital holographic image-taking apparatuses are known as disclosed in, for example, in Patent Literature (PTL) 1 and PTL 2. PTL 1 discloses a digital holographic image-taking apparatus, which irradiates a sample with incoherent illumination light emitted from a light source formed of a light emitting diode, through a spatial filter having minute apertures, so as to capture, with the image sensor, an interference pattern formed between light passing through the sample and non-diffused light.
PTL 2 discloses a digital holographic image-taking apparatus, which irradiates a sample with coherent illumination light from a laser light source, and magnifies, via an object lens and an eyepiece lens, an interference pattern between light scattered by the sample and light not scattered by the sample, so as to capture an interference pattern by an image sensor.